1. Field of the Invention
The present invention relates to a member for a semiconductor manufacturing apparatus.
2. Description of the Related Art
In the field of semiconductor manufacturing apparatuses, alumina (Al2O3), aluminum nitride (AlN), and the like, which are dense ceramic, are used as a substrate for an electrostatic chuck. Production is performed in such a way that a high-frequency electrode is embedded in a ceramic substrate in order to generate plasma for semiconductor processing. Here, it is necessary that the electrode embedded in the ceramic substrate is electrically joined to a power feed terminal. As for this power feed terminal, a metal material having excellent electrical conductivity is used favorably. In general, the metal material has a large thermal expansion coefficient as compared with that of the ceramic. Therefore, in order to produce a product by being joined to the ceramic substrate, it is required that cracking resulting from a difference in thermal expansion coefficient between ceramic/metal does not occur at the time of joining and, in addition, high joint strength is ensured for the reliability of the product. As for such a joining material, for example, indium is used in PTLs 1 and 2. Consequently, the ceramic substrate can be joined to the power feed terminal with sufficiently high joint strength. Furthermore, indium is soft and, therefore, an occurrence of cracking in the ceramic substrate can be suppressed.